Chromophobe renal cell carcinoma with massive sarcomatoid differentiation

Chromophobe renal cell carcinoma (CRCC) is a distinct subtype of renal cell carcinoma with unique histological, immunohistochemical, cytogenetic, and ultrastructural features, which usually has a favorable clinical course, with only a small percentage of patients developing recurrence, metastasis, or death due to its complications. Sarcomatoid differentiation can occur in any subtype of renal cell carcinoma and currently represents the transformation into a higher degree of malignancy, its presence being associated with a reserved prognosis, with a reported incidence of average survival of less than 1 year after diagnosis. In this study, we present an unusual case of CRCC with massive sarcomatoid differentiation, which infiltrated the left adrenal gland and was surgically resected. The histological features of this tumor as well as a brief review of literature are presented.